143 research outputs found
Efficacy of albendazole against the whipworm Trichuris trichiura - a randomised, controlled trial
Objectives and design. To test the efficacy of albendazole against the whipworm Trichuris trichiura for school-based deworming in the south-western Cape, South Africa. Children infected with Trichuris were randomised to 3 doses of albendazole (400; 800 or 1 200 mg), each repeated 4 times. The boy I girl ratio was 1. A group not infected With worms was treated with placebo, creating a negative control. Subjects and setting. Pupils at a primary school serving a wineproducing area approximately 90 km east of Cape Town.Outcome measures. Trichuris cure rates and reduction in the number of eggs/gin faeces, as well as the infection dynamics of Trichuris and Ascaris during treatment with placebo.Results. Albendazole treatment was associated with Trichuris cure rates of 23% (400 mg), 56% (800 mg) and 67% (1 200 mg) after the final treatment. The corresponding reductions in the number of eggs/g of faeces were 96.8%, 99.3% and 99.7%. Environmental pollution by human faeces was confirmed because worm egg-negative children in the placebo group became egg-positive while the study was in progress.Conclusion. The 400 mg stat dose had a low Trichuris cure rate. To repeat the dose on 2 or 3 days would increase cost, reduce compliance and complicate management. Albendazole cannot be used in deworming programmes in South Africa because it is a Schedule 4 prescription medicine. De-scheduling is needed urgently, particularly because of high efficacy against hookworm in KwaZulu-Natal and neighbouring countries
Treatment of Helminth Co-Infection in Individuals with HIV-1: A Systematic Review of the Literature
Many people living in areas of the world most affected by the HIV/AIDS pandemic are also exposed to other common infections. Parasitic infections with helminths (intestinal worms) are common in Africa and affect over half of the population in some areas. There are plausible biological reasons why treating helminth infections in people with HIV may slow down the progression of HIV to AIDS. Thus, treating people with HIV for helminths in areas with a high prevalence of both HIV and helminth infections may be a feasible strategy to help people with HIV delay progression of their disease or initiation of antiretroviral therapy. After a comprehensive review of the available literature, we conclude that there is not enough evidence to determine whether treating helminth infections in people with HIV is beneficial
The presence of serum anti-Ascaris lumbricoides IgE antibodies and of Trichuris trichiura infection are risk factors for wheezing and/or atopy in preschool-aged Brazilian children
<p>Abstract</p> <p>Background</p> <p>The elucidation of factors that trigger the development of transient wheezing in early childhood may be an important step toward understanding the pathogenesis of asthma and other allergic diseases later in life. Transient wheezing has been mainly attributed to viral infections, although sensitisation to aeroallergens and food allergens may occur at an early age. In developing countries, intestinal helminthic infections have also been associated with allergy or atopy-related disorders.</p> <p>Objective</p> <p>The aim of this study was to explore the association of <it>Trichuris trichiura </it>and <it>Ascaris lumbricoides </it>infections with wheezing and atopy in early childhood.</p> <p>Study design</p> <p>A cross-sectional study using a Portuguese-language ISAAC phase I questionnaire, adapted for preschool-aged children, nested in a cohort study of childhood diarrhoea, was conducted on 682 children. Two faecal samples per child were examined for the presence of intestinal helminthic infection. IgE antibodies against three allergenic preparations <it>(Dermatophagoides pteronyssinus, Blomia tropicalis </it>and common child food), as well as against <it>A. lumbricoides </it>antigens, were measured in a sub-sample of these children, whose parents allowed the procedure. Atopy was defined by the presence of levels of serum IgE antibodies ≥0.35 kU/L against at least one of the three tested allergenic preparations.</p> <p>Results</p> <p>Active <it>T. trichiura </it>infection but not <it>A. lumbricoides </it>infection was positively associated with wheezing in the total studied children population [adjusted OR = 2.60; CI = 1.54;4.38] and in the atopic children sub-population [adjusted OR = 3.07; CI = 1.00;9.43]. The association with atopy was also positive and statistically significant only in the brute analysis [OR = 2.13; CI = 1.03;4.40]. Anti-<it>A. lumbricoides </it>IgE antibodies, but not current <it>A. lumbricoides </it>infection, were positively associated with wheezing in atopic children [adjusted OR = 2.01; CI = 1.00;4.50] and in non-atopic children [adjusted OR = 3.07; CI = 1.13;8.35] and it was also associated with atopy [adjusted OR = 7.29; CI = 3.90; 13.4]. On the other hands, reports of wheezing were not significantly associated with atopy.</p> <p>Conclusions</p> <p>These data corroborate previous studies showing that wheezing is predominantly associated with infection in early childhood and shows that anti-<it>A. lumbricoides </it>IgE antibodies, but not active <it>Ascaris </it>infections, are associated with wheezing and atopy. Additionally, the data demonstrate that <it>T. trichiura </it>infection may play a role in the pathogenesis of atopic wheezing in early childhood.</p
The influence of different helminth infection phenotypes on immune responses against HIV in co-infected adults in South Africa
<p>Abstract</p> <p>Background</p> <p>The convergent distribution of the Human Immunodeficiency Virus (HIV) and helminth infections has led to the suggestion that infection with helminths exacerbates the HIV epidemic in developing countries. In South Africa, it is estimated that 57% of the population lives in poverty and carries the highest burden of both HIV and helmith infections, however, the disease interactions are under-researched.</p> <p>Methods</p> <p>We employed both coproscopy and <it>Ascaris lumbricoides</it>-specific serum IgE to increase diagnostic sensitivity and to distinguish between different helminth infection phenotypes and their effects on immune responses in HIV co-infected individuals. Coproscopy was done by formol ether and Kato Katz methods. HIV positive and negative adults were stratified according to the presence or absence of <it>A. lumbricoides </it>and/or <it>Trichuris trichuria </it>eggs with or without elevated <it>Ascaris </it>IgE. Lymphocyte subsets were phenotyped by flow cytometry. Viral loads, serum total IgE and eosinophils were also analysed. Lymphocyte activation markers (CCR5, HLA-DR, CD25, CD38 and CD71) were determined. Non parametric statistics were used to describe differences in the variables between the subgroups.</p> <p>Results</p> <p>Helminth prevalence ranged between 40%-60%. Four distinct subgroups of were identified, and this included egg positive/high <it>Ascaris</it>-specific IgE (egg<sup>+</sup>IgE<sup>hi</sup>), egg positive/low IgE (egg<sup>+</sup>IgE<sup>lo</sup>), egg negative/high IgE (egg<sup>-</sup>IgE<sup>hi</sup>) and egg negative/low IgE (egg<sup>-</sup>IgE<sup>lo</sup>) individuals. The egg<sup>+</sup>IgE<sup>hi </sup>subgroup displayed lymphocytopenia, eosinophilia, (low CD4<sup>+ </sup>counts in HIV<sup>- </sup>group), high viral load (in HIV<sup>+ </sup>group), and an activated lymphocyte profile. High <it>Ascaris </it>IgE subgroups (egg<sup>+</sup>IgE<sup>hi </sup>and egg<sup>-</sup>IgE<sup>hi</sup>) had eosinophilia, highest viral loads, and lower CD4<sup>+ </sup>counts in the HIV<sup>- </sup>group). Egg excretion and low IgE (egg<sup>+</sup>IgE<sup>lo</sup>) status demonstrated a modified Th<sub>2 </sub>immune profile with a relatively competent response to HIV.</p> <p>Conclusions</p> <p>People with both helminth egg excretion and high <it>Ascaris</it>-IgE levels had dysregulated immune cells, high viral loads with more immune activation. A modified Th<sub>2 </sub>helminth response in individuals with egg positive stools and low <it>Ascaris </it>IgE showed a better HIV related immune profile. Future research on helminth-HIV co-infection should include parasite-specific IgE measurements in addition to coproscopy to delineate the different response phenotypes. Helminth infection affects the immune response to HIV in some individuals with high IgE and egg excretion in stool.</p
Linking Global HIV/AIDS Treatments with National Programs for the Control and Elimination of the Neglected Tropical Diseases
Interaction of enamel matrix proteins with human periodontal ligament cells
Dorothy Hodgkin Postgraduate Award for research
studies (jointly funded by the Engineering and Physical Sciences Research
Council, UK, and by Institut Straumann) and the Research Discretionary
Funds of the Periodontology Unit, UCL Eastman Dental Institute.
Financial support was also provided by the NIHR Comprehensive
Biomedical Research Centre and by the WCU Program of the National
Research Foundation of Korea (NRF) funded by the Ministry of Education,
Science and Technology (No. R31-10069)
Reporting Guidelines for Survey Research: An Analysis of Published Guidance and Reporting Practices
Carol Bennett and colleagues review the evidence and find that there is limited guidance and no consensus on the optimal reporting of survey research
Schistosoma mansoni Enhances Host Susceptibility to Mucosal but Not Intravenous Challenge by R5 Clade C SHIV
Parasitic infections have been postulated to increase host susceptibility to HIV-1. We previously demonstrated that rhesus monkeys with active schistosomiasis were significantly more likely to become systemically infected after intrarectal exposure to an R5-tropic clade C simian-human immunodeficiency virus then were parasite-free control animals. However, we could not address whether parasites exert their effect at the mucosal level or systemically. To address the latter possibility, we measured the virus doses needed to achieve systemic infection after intravenous exposure of parasite-free or parasite-positive monkeys using the identical virus stock. None of the viral parameters tested in these two groups of monkeys were statistically significantly different. These results suggest that schistosomiasis modulates susceptibility to immunodeficiency virus acquisition predominantly at the mucosal level. Treatment for parasitic infections in populations at higher risk for HIV-1 acquisition could represent a cost-effective approach to slow the spread of HIV-1, which is predominantly transmitted through mucosal routes
A Knockout of the Tsg101 Gene Leads to Decreased Expression of ErbB Receptor Tyrosine Kinases and Induction of Autophagy Prior to Cell Death
The Tumor Susceptibility Gene 101 (Tsg101) encodes a multi-domain protein that mediates a variety of molecular and biological processes including the trafficking and lysosomal degradation of cell surface receptors. Conventional and conditional knockout models have demonstrated an essential requirement of this gene for cell cycle progression and cell viability, but the consequences of a complete ablation of Tsg101 on intracellular processes have not been examined to date. In this study, we employed mouse embryonic fibroblasts that carry two Tsg101 conditional knockout alleles to investigate the expression of ErbB receptor tyrosine kinases as well as stress-induced intracellular processes that are known to be associated with a defect in growth and cell survival. The conditional deletion of the Tsg101 gene in this well-controlled experimental model resulted in a significant reduction in the steady-state levels of the EGFR and ErbB2 but a stress-induced elevation in the phosphorylation of mitogen activated protein (MAP) kinases independent of growth factor stimulation. As part of an integrated stress response, Tsg101-deficient cells exhibited extensive remodeling of actin filaments and greatly enlarged lysosomes that were enriched with the autophagy-related protein LC3. The increase in the transcriptional activation and expression of LC3 and its association with Lamp1-positive lysosomes in a PI3K-dependent manner suggest that Tsg101 knockout cells utilize autophagy as a survival mechanism prior to their ultimate death. Collectively, this study shows that a knockout of the Tsg101 gene causes complex intracellular changes associated with stress response and cell death. These multifaceted alterations need to be recognized as they have an impact on defining particular functions for Tsg101 in processes such as signal transduction and lysosomal/endosomal trafficking
Free Radicals, Salicylic Acid and Mycotoxins in Asparagus After Inoculation with Fusarium proliferatum and F. oxysporum
Electron paramagnetic resonance was used to monitor free radicals and paramagnetic species like Fe, Mn, Cu generation, stability and status in Asparagus officinalis infected by common pathogens Fusarium proliferatum and F. oxysporum. Occurrence of F. proliferatum and F. oxysporum, level of free radicals and other paramagnetic species, as well as salicylic acid and mycotoxins content in roots and stems of seedlings were estimated on the second and fourth week after inoculation. In the first term free and total salicylic acid contents were related to free radicals level in stem (P = 0.010 and P = 0.033, respectively). Concentration of Fe3+ ions in porphyrin complexes (g = 2.3, g = 2.9) was related to the species of pathogen. There was no significant difference between Mn2+ concentrations in stem samples; however, the level of free radicals in samples inoculated with F. proliferatum was significantly higher when compared to F. oxysporum
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